Water level sensing apparatus of dish washer

ABSTRACT

Disclosed is a water level sensing apparatus of a dish washer comprising, a wash tub for containing dishware and a water level sensor disposed in the wash tub and moved in its position according to a water level in the wash tub, alternately comprising, a wash tub for containing dishware a float disposed in the wash tub and ascending/descending according to a water level of the wash tub and a sensing unit sensing a water level corresponding to a position of the float. 
     According to the water level sensing apparatus of the dish washer, it is capable of minimizing influence on a capacity of the wash tub caused by installation of the water level sensor, of precisely sensing the amount of water in the wash tub and of implement the float stably ascending/descending.

RELATED APPLICATION

The present disclosure relates to subject matter contained in priority Korean Application No. 10-2007-0089680, filed on Sep. 4, 2007 which is herein expressly incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a dishwasher, and particularly, to a water level sensing apparatus of a dishwasher.

2. Background of the Invention

A dishwasher is a machine for washing garbage remaining on a dishware (e.g., dishes, cups, bowls and the like) by spraying a high pressure of washing water onto the dishes contained in a wash tub or washing chamber. Such dishwasher is configured such that dishes are washed off using washing water containing detergent and the washed dishes are dried.

In order to sense the amount of supplied water, a method for sensing the amount of the supplied water using a flow meter is applied to the conventional dish washer. The flow meter is installed outside of a wash tub so as to sense the amount of the supplied water.

According to the conventional method using the flow meter, as the flow meter is installed outside of the wash tub, a size of the wash tub is reduced as large as an installation space for the flow meter, accordingly space utilization may be deteriorated.

And, as the flow meter installed outside of the washing tub is connected to the washing tub by a connection pipe, water may leak from the connected portion. The leakage may cause the dish washer to be out of order and to be unable to precisely sense the amount of water.

And, if the conventional sensing method is applied to a case that a small amount of water is used, e.g., small-sized dish washer, it may be difficult to precisely sense the amount of washing water.

SUMMARY OF THE INVENTION

Therefore, one object of the present invention is to provide a water level sensing apparatus of a dish washer which is capable of minimizing influence on a capacity of a wash tub and of precisely sensing the amount of water.

In one aspect of the present invention, there is provided a water level sensing apparatus of a dish washer, comprising: a wash tub for containing dishware and a water level sensor disposed in the wash tub and moved in its position according to a water level in the wash tub.

In another aspect of the present invention, there is provided a water level sensing apparatus of a dish washer, comprising: a wash tub for containing dishware, a float disposed in the wash tub and ascending/descending according to a water level of the wash tub and a sensing unit sensing a water level corresponding to a position of the float.

According to the water level sensing apparatus of the dish washer in accordance with the present invention, the water level sensing apparatus includes the water level sensor composed of the float and the sensing unit and moved in its position according to the water level in the wash tub by being disposed in the wash tub, accordingly it is not required to additionally attach a sensor at an outside of the wash tub for sensing the water level in the wash tub. Accordingly, it is not required for a separate space for installing the water level sensor at the outside of the wash tub, thereby being capable of maximizing a capacity of the wash tub. Thus, it is capable of minimizing influence on the capacity of the wash tub caused by installation of the water level sensor, and of precisely sensing the amount of water in the wash tub.

And, according to the water level sensing apparatus of the dish washer, a cover is configured to encompass the float and a washing water inflow hole is formed at a lower end of the cover. The washing water is introduced therethrough and it is capable of preventing the washing water from flowing into other portions. Thus, the cover can prevent the float from being affected by a flowing force of the washing water, e.g., waves on a surface of the washing water. Accordingly, it is capable of precisely sensing the water level in the wash tub and stably ascending/descending the float in the cover.

And, according to the water level sensing apparatus of the dish washer, an adhesion preventing unit is interposed between the float and the wash tub, accordingly the float does not directly contact the wash tub but contacts the adhesion preventing unit when the float descends. Thus, a contact area between the float and the wash tub is reduced, thereby preventing the float from being adhered to the wash tub by moisture. Accordingly, it is capable of preventing a phenomenon that the float does not facilitatingly ascend resulting from that it adheres to a bottom surface of the wash tub when the water level rises and then the float ascends again.

And, according to the water level sensing apparatus of the dish washer, as a protrusion is protruded from an upper end surface of the float toward the lower end of the cover by a specific height, the float does not directly contact the cover when it ascends. Accordingly, it is capable of preventing a phenomenon that the float does not facilitatingly operate resulting from that it adheres to the cover.

The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

In the drawings:

FIG. 1 is a schematic view showing a dish washer in accordance with a first exemplary embodiment of the present invention;

FIG. 2 is a perspective view showing a disassembled status of a float adapted to a water level sensing apparatus of the dish washer in accordance with the first exemplary embodiment of the present invention;

FIG. 3 is a section view partially showing a wash tub at which a sensing unit adapted to the water level sensing apparatus of the dish washer is disposed in accordance with the first exemplary embodiment of the present invention;

FIG. 4 is a section view showing that the float senses a zero level in accordance with the first exemplary embodiment of the present invention;

FIG. 5 is a section view showing that the float of FIG. 4 senses a normal level;

FIG. 6 is a section view showing that the float of FIG. 5 senses an oversupply level;

FIG. 7 is a perspective view showing a cover adapted to a water level sensing apparatus of a dish washer in accordance with a second exemplary embodiment of the present invention;

FIG. 8 is a section view showing that the cover is disposed in accordance with the second exemplary embodiment of the present invention;

FIG. 9 is a section view showing that an adhesion preventing unit is adapted to a water level sensing apparatus of a dish washer in accordance with a third exemplary embodiment of the present invention;

FIG. 10 is a perspective view showing the adhesion preventing unit in accordance with the third exemplary embodiment of the present invention;

FIG. 11 is a perspective view showing a float adapted to a water level sensing apparatus of a dish washer in accordance with a fourth exemplary embodiment of the present invention;

FIG. 12 is a section view showing that the float is mounted to a wash tub in accordance with the fourth exemplary embodiment of the present invention; and

FIG. 13 is a perspective view showing a disassembled status of a float adapted to a water level sensing apparatus of a dish washer in accordance with a fifth exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Description will now be given in detail of the present invention, with reference to the accompanying drawings.

FIG. 1 is a schematic view showing a dish washer in accordance with a first exemplary embodiment of the present invention.

Referring to FIG. 1, a dish washer 100 in accordance with the first exemplary embodiment of the present invention includes: a wash tub 110 installed inside a case 101, a door 102 for opening/closing the wash tub 110, and a rack 103 installed in the wash tub 110 for containing dishware (e.g., dishes, cups, bowls, and the like).

Also, the dish washer 100 further includes a sump 106 installed in a lower portion of the wash tub 110 for containing washing water, an impeller 107 configured to pump the washing water contained in the sump 106, and a washing motor 108 for driving the impeller 107.

The dish washer 100 further includes a nozzle apparatus 200 for spraying the washing water pumped from the sump 120 onto the dishware to be washed off, and a rotary nozzle 104. The nozzle apparatus 200 is fixed to a rear side of the wash tub 110 so as to spray the washing water onto the dishware. And, the rotary nozzle 104 is rotated by a spraying pressure of the washing water below the rack 103, thus to spray the washing water onto the dishware. By spraying the washing water, garbage on the dishes can be removed and thusly the dishes can be washed off.

FIG. 2 is a perspective view showing a disassembled state of a float adapted to a water level sensing apparatus of the dish washer in accordance with the first exemplary embodiment of the present invention, and FIG. 3 is a section view partially showing a wash tub at which the sensing unit adapted to the water level sensing apparatus of the dish washer is disposed in accordance with the first exemplary embodiment of the present invention.

Referring to FIGS. 2 and 3, the float 200 adapted to the water level sensing apparatus of the dish washer in accordance with this embodiment includes a floating body 210, connecting rods 220, rotation shafts 231, a magnet anchoring unit 250, and a magnet 260. The float 200 is disposed in the wash tub 110, and ascends/descends according to a water level in the wash tub 110.

And, the wash tub 110 of the dish washer is provided with a shaft coupling unit 120 and a sensing unit. The shaft coupling unit 120 is provided with a shaft insertion holes 121. The sensing unit may include a zero level sensing part 150, a normal level sensing part 151 and an oversupply level sensing part 152. The sensing unit senses a water level corresponding to a position of the float 200 ascending and descending. A lead sensor may be used for the sensing unit.

The float 200 and the sensing unit are disposed in the wash tub 110 so as to sense the water level in the wash tub 110. In this aspect, the float 200 and the sensing unit can be defined as a water level sensor.

The floating body 210 implemented as a foam, accordingly it can float on water. The floating body 210 ascends or descends according to the water level in the wash tub, thereby being capable of sensing the water level.

The rotation shafts 231 are connected to the floating body 210 through the connecting rods 220. Shaft holders 230 are formed at each end of the connecting rods 220. And, the rotation shafts 231 are protruded from the rotation holders 230. The rotation shafts 231 are rotatably inserted into the shaft insertion holes 121 formed at the shaft coupling unit 120 of the wash tub 110.

A reference numeral 240 denotes a rod support connecting the plurality of connecting rods 220 to each other thus to enhance rigidity thereof.

The float 200 is coupled to the wash tub 110 through the rotation shafts 231 and the shaft insertion holes 121 by hinges thus to be operated within a specific range. The coupling by the hinge is merely an example of a coupling manner of the float 200 with respect to the wash tub 110. There may be various manners for connecting the float 200 to the wash tub 110 so as for the float to be operable within the specific range.

The magnet anchoring unit 250 is provided under the floating body 210. The magnet insertion hole 251 is formed therein. The magnet 260 is inserted into the magnet insertion hole 251. The lead sensor of the sensing unit reacts to the magnet 260, accordingly it is capable of sensing the water level in the wash tub 110.

The magnet anchoring unit 250 is formed at a position where the magnet 260 is disposed on a line vertically passing through a center of gravity of the float 200. Then, it is capable of preventing the float 200 from being inclined by a weight of the magnet 260 and of maintaining a stable status during operation.

The connecting rods 220, the shaft holders 230, the rotation shafts 231, the rod support 240 and the magnet anchoring unit 250 may be implemented as a foam to be integral with the floating body 210 by an integrally foaming manner. Accordingly, the float 200 may easily float on washing water and be easily fabricated.

The shaft coupling unit 120 is formed at the wash tub 110. The shaft insertion holes 121 are formed at the shaft coupling unit 120, and the rotation shafts 231 of the float 200 are rotatably coupled to the shaft insertion holes 121. That is, the shaft insertion holes 121 and the rotation shafts 231 serve as a rotation center of the float 200.

The sensing unit is disposed on a wall surface of the wash tub 110 so as to sense the water level corresponding to a position of the float 200. In detail, the zero level sensing part 150, the normal level sensing part 151 and the oversupply level sensing part 152 are spaced from each other by a specific distance therebetween on a specific radius (R) centering the shaft insertion holes 121.

Accordingly, each of the sensing parts interacts with the float 200 so as to sense the water level in the wash tub 110. This will be explained with reference to FIGS. 4 to 6.

Here, it discloses that the sensing parts sense a zero level, a normal level and an oversupply level in the wash tub 110, but this is exemplary. That is, the sensing parts are disposed at positions corresponding to a water level required to be sensed so as to sense the required level. The required level may be one of the levels or be various levels.

FIGS. 4 to 6 show operation of the water level sensing apparatus of the dish washer in accordance with the first exemplary embodiment of the present invention.

FIG. 4 is a section view showing that the float senses a zero level in accordance with the first exemplary embodiment of the present invention, FIG. 5 is a section view showing that the float of FIG. 4 senses a normal level, and FIG. 6 is a section view showing that the float of FIG. 5 senses an oversupply level.

Hereafter, the operation of the water level sensing apparatus in accordance with this embodiment with reference to FIGS. 4 to 6.

First, as shown in FIG. 4, in a state that the float 200 is located at a bottom of the wash tub 110, the magnet 260 of the float 200 faces the zero level sensing part 150 to each other. Thus, the zero level sensing part 150 senses the zero level in the wash tub 110.

Then, if the water level rises as the wash tub 110 is gradually filled with the washing water, the float 200 may ascend. Upon ascending, as shown in FIG. 5, when the magnet 260 reaches a position facing the normal level sensing part 151, the normal level sensing part 151 senses that the water level is normal in the wash tub 110. Here, a controller (not shown) may transfer signals indicating to stop supplying the washing water into the wash tub 110 to a water supply system.

Thereafter, if the water level further rises as the wash tub 110 is further filled with the washing water caused by the washing water continuously supplied into the wash tub 110, the float 200 may further ascend. Upon ascending, as shown in FIG. 6, when the magnet 260 reaches a position facing the oversupply level sensing part 152, the oversupply level sensing part 152 senses that the water is excessively supplied into the wash tub 110. Here, the controller may transfer signals indicating to partially drain the washing water in the wash tub 110 to a drain system.

As such, the water level sensor composed of the float 200 and the sensing unit is disposed in the wash tub 110 and then senses the water level in the wash tub 110, accordingly it is not required to additionally attach a sensor at an outside of the wash tub 110 for sensing the water level in the wash tub 110. Thus, it is not required for a separate space for installing the water level sensor at the outside of the wash tub 110, accordingly a capacity of the wash tub 110 can be maximized. Accordingly, it is capable of minimizing influence on the capacity of the wash tub 110 caused by installation of the water level sensor and of precisely sensing the amount of water in the wash tub 110.

Hereafter, other exemplary embodiments of the present invention will be explained with reference to accompanying drawings. Description same as that of the first exemplary embodiment will be omitted.

FIG. 7 is a perspective view showing a cover adapted to a water level sensing apparatus of a dish washer in accordance with a second exemplary embodiment of the present invention, and FIG. 8 is a section view showing that the cover is disposed in accordance with the second exemplary embodiment of the present invention.

Referring to FIGS. 7 and 8, in this embodiment, the float 200 is coupled to the shaft coupling units 120 of the wash tub 110 by hinges, and a cover 300 covers an upper side of the float 200.

The cover 3001 as shown in FIG. 7, encompasses the float 200. A washing water inflow hole 320 is formed between a lower end of the cover 300 and a bottom surface of the wash tub 110. By this washing water inflow hole 320, the washing water is introduced into a lower side of the float 200 therethrough, and it is capable of preventing the washing water from flowing into other portions. Thus, the cover 300 can prevent the float 200 from being affected by a flowing force of the washing water, e.g., waves on a surface of the washing water. Accordingly, it is capable of precisely sensing the water level in the wash tub 110 and stably ascending/descending the float 200 in the cover 300.

Since the cover 300 encompasses the float 200, it is capable of minimizing a phenomenon that the float 200 is polluted by garbage in the washing water contained in the wash tub 110.

In this aspect, since the cover 300 serves to prevent the water level sensor composed of the float 200 and the sensing unit from being polluted, it can be defined as a pollution preventing unit. Hereafter, other components serving to prevent the water level sensor from being polluted also can be defined as the pollution preventing unit.

A reference numeral 310 denotes a floating hole forming unit forming a space for ascending/descending the float 200 therein.

FIG. 9 is a section view showing that an adhesion preventing unit is adapted to a water level sensing apparatus of a dish washer in accordance with a third exemplary embodiment of the present invention, and FIG. 10 is a perspective view showing the adhesion preventing unit in accordance with the third exemplary embodiment of the present invention.

Referring to FIGS. 9 and 10, the adhesion preventing unit 112 is applied to the water level sensing apparatus of the this embodiment.

The adhesion preventing unit 112 formed in a protrusion shape protruded from a bottom surface 111 of the wash tub 110 by a specific height and contacts the descending float 200. Preferably, the adhesion preventing unit 112 point-contacts the float 200.

As the float 200 descends and contacts the adhesion preventing unit 112, the float 200 does not directly contact the wash tub 110. Accordingly, a contact area between the float 200 and the wash tub 110 is reduced, thereby preventing the float 200 from being adhered to the wash tub 110 by moisture. Accordingly, it is capable of preventing a phenomenon that the float 200 does not facilitatingly ascend resulting from that it adheres to the bottom surface 111 of the wash tub 110 when the water level rises and then the float 200 ascends again.

And, the adhesion preventing unit 112 prevents the float 200 from directly contacting the bottom surface 111 of the wash tub 110, accordingly it is capable of preventing the float 200 from being polluted by garbage in the washing water which may sink to the bottom surface 111 and be piled up thereon.

Here, the adhesion preventing unit 112 is disclosed as a protrusion protruded from the bottom surface 111 of the wash tub 110, however it is merely exemplary. That is, the protrusion may be formed at the lower portion of the float 200 or formed at both of the float 200 and the wash tub 110.

FIG. 11 is a perspective view showing a float adapted to a water level sensing apparatus of a dish washer in accordance with a fourth exemplary embodiment of the present invention, and FIG. 12 is a section view showing that the float is mounted to a wash tub in accordance with the fourth exemplary embodiment of the present invention.

Referring to FIGS. 11 and 12, in this embodiment, the cover 200 covers the upper side of the float 200 and a protrusion 211 is formed on an upper end surface of the float 200.

The protrusion 211 is protruded from the upper end surface of the float 200 toward the lower end of the cover 300 by a specific height, and directly contacts the cover 300 when the float 200 ascends. The protrusion 211 point-contacts the cover 300, preferably. The protrusion 211 may be formed in plural in number on the upper end surface of the float 200.

By the protrusions 211, the float 200 does not directly contact the cover 300 when the float 200 ascends. Accordingly, it is capable of preventing the phenomenon that the float 200 does not facilitatingly operate resulting from that it adheres to the cover 300.

And, by the protrusions 211, it is capable of preventing the float 200 from directly contacting the cover 300, thereby being capable of preventing the upper portion of the float 200 from being polluted.

Here, the protrusions 211 are disclosed that they are protruded from the upper end surface of the float 200, however it is exemplary. That is, the protrusions 211 may be protruded from a lower end surface of the cover 300 or be formed at both of the float 200 and the cover 300.

FIG. 13 is a perspective view showing a disassembled status of a float adapted to a water level sensing apparatus of a dish washer in accordance with a fifth exemplary embodiment of the present invention.

Referring to FIG. 13, a float 400 applied to the water level sensing apparatus in this embodiment includes a floating body 410 as a foam, and a floating case 420 having an internal groove 421 into which the floating body 410 is inserted as a non-foam.

The floating case 420 is integrally formed with connecting rods 430, a rod support 440, shaft holders 450, and rotation shafts 451. Since each component is same as that of the first exemplary embodiment, it will be omitted.

The float 400 may ascend/descend according to the water level in the wash tub 110 by buoyancy of the floating body 410 inserted into the floating case 420.

According to the water level sensing apparatus of the dish washer in accordance with the present invention, the water level sensor composed of the float and the sensing unit is disposed in the wash tub and thus senses the water level in the wash tub, accordingly it is not required to additionally attach a sensor at the outside of the wash tub for sensing the water level in the wash tub. Accordingly, it is not required for a separate space for installing the water level sensor at the outside of the wash tub, thereby being capable of maximizing the capacity of the wash tub. Thus, it is capable of minimizing influence on the capacity of the wash tub caused by installation of the water level sensor, and of precisely sensing the amount of water in the wash tub.

And, according to the water level sensing apparatus of the dish washer, the cover is configured to encompass the float and the washing water inflow hole is formed at the lower end of the cover. The washing water is introduced therethrough and it is capable of preventing the washing water from flowing into other portions. Thus, the cover can prevent the float from being affected by a flowing force of the washing water, e.g., waves on a surface of the washing water. Accordingly, it is capable of precisely sensing the water level in the wash tub and stably ascending/descending the float in the cover.

And, according to the water level sensing apparatus of the dish washer, the adhesion preventing unit is interposed between the float and the wash tub, accordingly the float does not directly contact the wash tub but contacts the adhesion preventing unit when the float descends. Thus, the contact area between the float and the wash tub is reduced, thereby preventing the float from being adhered to the wash tub by moisture. Accordingly, it is capable of preventing a phenomenon that the float does not facilitatingly ascend resulting from that it adheres to the bottom surface of the wash tub when the water level rises and then the float ascends again.

And, according to the water level sensing apparatus of the dish washer, as the protrusion is protruded from the upper end surface of the float toward the lower end of the cover by a specific height, the float does not directly contact the cover when it ascends. Accordingly, it is capable of preventing the phenomenon that the float does not facilitatingly operate resulting from that it adheres to the cover.

The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.

As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims. 

1. A water level sensing apparatus of a dish washer, comprising: a wash tub for containing dishware; and a water level sensor disposed in the wash tub and moved in its position according to a water level in the wash tub.
 2. The apparatus of claim 1, wherein the water level sensor comprises a float ascending/descending according to the water level in the wash tub, and a sensing unit sensing the water level corresponding to a position of the float.
 3. The apparatus of claim 1, further comprises a cover covering the water level sensor.
 4. The apparatus of claim 3, wherein a washing water inflow hole is formed at a lower side of the cover so as to supply washing water to a lower side of the water level sensor.
 5. The apparatus of claim 4, wherein the washing water inflow hole is formed between a lower end of the cover and a bottom surface of the wash tub.
 6. A water level sensing apparatus of a dish washer, comprising: a wash tub for containing dishware; a float disposed in the wash tub and ascending/descending according to a water level of the wash tub; and a sensing unit sensing a water level corresponding to a position of the float.
 7. The apparatus of claim 6, wherein the float is connected to the wash tub so as to be operable within a specific range.
 8. The apparatus of claim 7, wherein the float is coupled to the wash tub by hinges.
 9. The apparatus of claim 6, wherein a magnet and a lead switch are respectively disposed to the float and the sensing unit corresponding thereto.
 10. The apparatus of claim 9, wherein the magnet is disposed at the float and the lead switch is disposed at the sensing unit.
 11. The apparatus of claim 9 or 10, wherein the magnet is disposed on a line vertically passing through a center of gravity of the float.
 12. The apparatus of claim 6, wherein the sensing unit is disposed at a position corresponding to a water level to be sensed in the wash tub.
 13. The apparatus of claim 12, wherein the water level to be sensed is at least one of a normal level, an oversupply level, a zero level of the wash tub.
 14. The apparatus of claim 6, wherein an adhesion preventing unit is installed between the wash tub and the float so as to prevent the flow from being adhered to a specific portion of the wash tub.
 15. The apparatus of claim 14, wherein the adhesion preventing unit comprises a protrusion formed at least one of the float and the portions of the wash tub facing the float.
 16. The apparatus of claim 6, wherein the float is implemented as a foam.
 17. The apparatus of claim 16, wherein the float is connected to the wash tub by a connection unit integrally formed with the float in a foaming manner.
 18. The apparatus of claim 16, further comprises a float case in which the float is installed and connected to the wash tub. 